[PATCH v6 2/5] dt-bindings: pwm-backlight: add PWM delay proprieties.
Enric Balletbo i Serra
enric.balletbo at collabora.com
Mon Mar 26 02:52:10 PDT 2018
Hardware needs a delay between setting an initial (non-zero) PWM and
enabling the backlight using GPIO. The post-pwm-on-delay-ms specifies
this delay in milli seconds. Hardware also needs a delay between disabing
the backlight using GPIO and setting PWM value to 0. The pwm-off-delay-ms
is this delay in milli seconds.
Signed-off-by: Enric Balletbo i Serra <enric.balletbo at collabora.com>
Acked-by: Pavel Machek <pavel at ucw.cz>
Acked-by: Thierry Reding <thierry.reding at gmail.com>
Based on the original Huang Lin <hl at rock-chips.com> work.
Changes since v5:
- Add Acked-by: Thierry Reding <thierry.reding at gmail.com>
- CC DT mainling list (for some reason dropped at some point, my
Changes since v4:
- Rebase on top of mainline.
Changes since v3:
- Replace us for ms.
- Add Acked-by: Pavel Machek <pavel at ucw.cz>
Changes since v2:
- Use separate properties (Rob Herring)
Changes since v1:
- As suggested by Daniel Thompson
- Do not assume power-on delay and power-off delay will be the same
Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt b/Documentation/devicetree/bindings/leds/backlight/pwm-backlight.txt
index 764db86d441a..310810906613 100644
@@ -17,6 +17,10 @@ Optional properties:
"pwms" property (see PWM binding)
- enable-gpios: contains a single GPIO specifier for the GPIO which enables
and disables the backlight (see GPIO binding)
+ - post-pwm-on-delay-ms: Delay in ms between setting an initial (non-zero) PWM
+ and enabling the backlight using GPIO.
+ - pwm-off-delay-ms: Delay in ms between disabling the backlight using GPIO
+ and setting PWM value to 0.
@@ -32,4 +36,6 @@ Example:
power-supply = <&vdd_bl_reg>;
enable-gpios = <&gpio 58 0>;
+ post-pwm-on-delay-ms = <10>;
+ pwm-off-delay-ms = <10>;
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